A visit to Mozambique is a chance to kayak among mangroves, dive the reefs and chill out in luxury. Kate Humble does it all – at the same time as being a responsible tourist.

Sulkily, the woman repeated herself: "We don't advise our members to go to Mozambique." I could feel my grip tightening on the counter. "I know," I said, "but if we do go, can you tell us whether we can buy fuel anywhere, or whether we should take it with us?"

"We don't advise..."

It was December 1994. South Africa had just had its first democratic elections, Namibia had recently gained its independence, and Mozambique was emerging cautiously from a long and bloody civil war. My husband Ludo and I had decided to celebrate the changing face of Southern Africa by driving a loop from Cape Town, through Namibia, Zimbabwe, Mozambique and Swaziland. It was a straightforward enough journey, complicated only by the fact that our vehicle was an ancient Ford Cortina with a gearstick that would suddenly detach itself from the rest of the car, usually when changing between third and fourth.

However, when we reached Mutare, the last big town in Zimbabwe before crossing the border into Mozambique, it wasn't just the woman in the AA office who tried to dissuade us from going.

We heard horror stories about the roads, ambushes, corrupt policemen, no fuel and no food. "And whatever you do," warned everyone we spoke to, "don't go to the north. There are mines everywhere and you'll need something a lot better than that wreck if you're going to make it."We didn't go to the north, but we did drive across the border to Beira and then turned south to Maputo and out into Swaziland. The roads weren't great, fuel and food were hard to find, but we weren't ambushed or ripped off. The car broke down three times, and on each occasion we were rescued by obliging locals who, with ingenuity and a few rusty spanners, managed to get it going again.

Mozambique was a country clearly on its knees. Buildings and infrastructure were crumbling, and much of the depleted population was maimed, hungry and desperately poor. But none of that took away from the fact that Mozambique, particularly its coastline and the numerous islands that dotted the channel, was beautiful. And unspoilt. And ripe for exploitation: already there were places springing up along the coast, built mainly by South Africans hoping to make a quick buck. Soon that southern half of the coastline was awash with resorts, hotels and hostels – and attention turned to the north. Mines were cleared, roads improved and the important port of Pemba became the new boom-town.

– has now become the place to go for barefoot luxury and sky-high prices. But has this influx of foreign investment and tourist dollars done much to improve the lot of ordinary Mozambicans? The answer, sadly, is probably no.

Building anything in Mozambique takes more time and money than many anticipate, and more projects have failed than succeeded. To include any sort of social responsibility, or provision to give something tangible back to the local population, is something that few investors include in their business plans, overwhelmed as they are by the enormity of getting everything else done. But there are exceptions to this rule….

… Built on the edge of a 2km crescent of untouched beach, it is a wonderful location – but it was the nearby village of Guludo that made it perfect for Amy Carter and Neal Allcock. This British couple wanted to take the idea of tourism supporting a local community further still. "Responsible tourism" has become something of a buzz-phrase recently, taking over from the once ubiquitous "eco-tourism".

Having stayed in a number of places purporting to be eco-lodges, and finding that they can be anything but, I wanted to find out whether a place built apparently with the intention of reducing poverty really did deliver – not just to local people but to those who, like me, are hoping for a peaceful, relaxing holiday.

The inhabitants of Guludo, like almost all rural communities in Mozambique, live hand-to-mouth, eating only what they catch or grow; few children get a chance to go to school; poverty, it seems, is inescapable. Carter and Allcock hoped that the lodge they were planning would change the long-term future of the village for the better. Stuck hundreds of miles to the south of Guludo in the Mozambican port city of Pemba, wrangling over legalities, licences, bewildering paperwork and spiralling costs, there must have been many times when their courage began to fail them, but the result is a beautiful place to stay – and a resource that has revitalised the area.

The bar, dining area and kitchen of the lodge are built from local materials, in the style of the village houses. They sit on a sandbank which rises up from the beach, cooled by sea breezes and shaded by palms. The rooms are spaced out beyond, overlooking the beach. Huge mosquito-net tents sit under triangular thatched roofs, giving a feeling of openness and privacy at the same time. Local wood, fabrics and crafts have been used as much as possible to furnish the rooms; and there are real touches of ingenuity, like shower-heads made from coconut shells.

A path leads down the bank to the beach, which curves away as far as the eye can see in both directions.

Between July and October, humpback whales pass through the bay during their annual migration. Beneath the surface, reefs and drop-offs make for great diving and the opportunity to swim, as we did, in the company of octopus, lionfish and whitetip reef sharks.

What makes this place so different from other barefoot luxury beach-resorts on the African coast is the opportunity to get an insight into the lives of local people. Visiting the village with Carter, it soon became clear that she knew everyone and that everyone knew – and loved – her.

Fifty-five villagers work at the lodge. Their uniforms, which they designed themselves, were made by the local tailor; he is nicknamed Deze Nove, meaning 19, because he has 10 toes but only nine fingers. All the fish eaten at the lodge is bought from village fishermen, and guests can go fishing with them to learn their techniques. Village women come to the lodge for those who want their hair braided, or a local facial using the pounded root that the woman smear on their faces to protect their skin from the sun and keep it soft.

Carter has set up a charity that is part-funded by the profits from her lodge. We saw the new well, drilled and managed by a village committee, and funded by the charity. We visited the site, under three huge mango trees, where a new primary school and community centre will be built to replace the roofless building that currently serves the village's students.

School was clearly far from the thoughts of the group of young boys that we later saw dancing and singing in front of their proud parents. We were invited to join this celebration to mark the return of the newly circumcised boys from their month-long exile in the bush, and their transition into manhood. I asked one of the men if, like some other African tribes, the boys had to remain silent during circumcision and not cry or even whimper. " No," he smiled. "It really hurts. You scream and scream."

At the mosque, we were put to work helping a group of women and children armed with machetes and rakes to clear waist-high grass and weeds from the compound.

"Where are the men?" we asked. "They should be doing all this heavy work." The women laughed. "We do it better."

The lodge has begun to change people's lives for the better. But did that make for a good holiday for worn-out Westerners? For Ludo and myself, the lodge was the perfect mix of comfort and simplicity. Five days of diving and reading, eating and lazing, in a place that felt so far from the bustle of the modern world, made us both feel we'd been away for a month. But the thing that set it apart was spending time in the village and seeing how our holiday was helping change the lives of the people who lived there.

Two British couples, who arrived a couple of days after us, had the foresight to ask Carter if there was anything useful they could bring with them. She'd suggested reading glasses, and so they'd had a whip-round among their myopic friends. Over dinner, they described their village visit and the joy of an old woman who put on a pair of cast-off spectacles and discovered, for the first time in years, that she could see clearly. It moved them to tears, and made this a holiday they'd never forget.

These days, you need not fret about taking fuel to northern Mozambique. A silver teaspoon and a pair of reading glasses will make all the difference.